NEW YORK—The largest U.S. power-grid operator is probing why suppliers were unable to deliver needed power during a late December storm when customers narrowly avoided outages as freezing temperatures descended, officials said on Thursday.
Generators that were unable to deliver increased electricity during three peak demand days in late December could face about $2 billion in penalties, stakeholders and analysts said.
Grid operator PJM Interconnection oversees supply in a 13-state region, managing and paying on-call generators to keep power systems running. When generators fail to meet supply, they may be required to pay the grid operator for replacement power.
PJM officials said on Thursday that more than 90 percent of the generators that fell short gave less than an hour’s notice during winter Storm Elliott. PJM acknowledged it underestimated demand by about 10 percent….